This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A170779 #23 Sep 08 2022 08:45:49
%S A170779 0,1,16512,7177734,536903680,15258984375,235093332096,2373783637372,
%T A170779 17592194433024,102945587570685,500000050000000,2088624191887266,
%U A170779 7703511002284032,25592946914910739,77784048516800640
%N A170779 a(n) = n^8*(n^7 + 1)/2.
%C A170779 Number of unoriented rows of length 15 using up to n colors. For a(0)=0, there are no rows using no colors. For a(1)=1, there is one row using that one color for all positions. For a(2)=16512, there are 2^15=32768 oriented arrangements of two colors. Of these, 2^8=256 are achiral. That leaves (32768-256)/2=16256 chiral pairs. Adding achiral and chiral, we get 16512. - _Robert A. Russell_, Nov 13 2018
%H A170779 Vincenzo Librandi, <a href="/A170779/b170779.txt">Table of n, a(n) for n = 0..10000</a>
%H A170779 <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (16, -120, 560, -1820, 4368, -8008, 11440, -12870, 11440, -8008, 4368, -1820, 560, -120, 16, -1).
%F A170779 G.f.: (x + 16496*x^2 + 6913662*x^3 + 424040816*x^4 + 7520608675*x^5 + 51388540128*x^6 + 155693747508*x^7 + 223769408736*x^8 + 155693850903*x^9 + 51388458800*x^10 + 7520620846*x^11 + 424050096*x^12 + 6911077*x^13 + 16256*x^14)/(1-x)^16. - _G. C. Greubel_, Dec 05 2017
%F A170779 From _Robert A. Russell_, Nov 13 2018: (Start)
%F A170779 a(n) = (A010803(n) + A001016(n)) / 2 = (n^15 + n^8) / 2.
%F A170779 G.f.: (Sum_{j=1..15} S2(15,j)*j!*x^j/(1-x)^(j+1) + Sum_{j=1..8} S2(8,j)*j!*x^j/(1-x)^(j+1)) / 2, where S2 is the Stirling subset number A008277.
%F A170779 G.f.: x*Sum_{k=0..14} A145882(15,k) * x^k / (1-x)^16.
%F A170779 E.g.f.: (Sum_{k=1..15} S2(15,k)*x^k + Sum_{k=1..8} S2(8,k)*x^k) * exp(x) / 2, where S2 is the Stirling subset number A008277.
%F A170779 For n>15, a(n) = Sum_{j=1..16} -binomial(j-17,j) * a(n-j). (End)
%F A170779 E.g.f.: x*(2 +16510*x +2376067*x^2 +42357651*x^3 +210767970*x^4 + 420693539*x^5 +408741361*x^6 +216627841*x^7 +67128490*x^8 + 12662650*x^9 +1479478*x^10 +106470*x^11 +4550*x^12 +105*x^13 +x^14)*exp(x)/2. - _G. C. Greubel_, Nov 15 2018
%t A170779 Table[n^8*(n^7+1)/2, {n,0,30}] (* _G. C. Greubel_, Dec 05 2017 *)
%o A170779 (Magma) [n^8*(n^7+1)/2: n in [0..30]]; // _Vincenzo Librandi_, Aug 26 2011
%o A170779 (PARI) for(n=0, 30, print1(n^8*(n^7+1)/2, ", ")) \\ _G. C. Greubel_, Dec 05 2017
%o A170779 (Sage) [n^8*(n^7+1)/2 for n in range(30)] # _G. C. Greubel_, Nov 15 2018
%Y A170779 Row 15 of A277504.
%Y A170779 Cf. A010803 (oriented), A001016 (achiral).
%K A170779 nonn,easy
%O A170779 0,3
%A A170779 _N. J. A. Sloane_, Dec 11 2009